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  2. Affordable System Operational Effectiveness (ASOE) Model

Affordable System Operational Effectiveness (ASOE) Model


Alternate Definition

The ASOE Model illustrates the dependency and interrelationship between technical performance, availability (i.e., reliability, maintainability, and supportability), process efficiency (i.e., system operations, maintenance, and logistics support), and Life Cycle Cost (LCC). The use of this model helps programs determine how well a system will be able to perform its missions over a sustained period as well as the ability to surge given the user's operating budget. In this model, the emphasis is on the system's ability to execute its mission and its reliability and maintainability and also on the cost effective responsiveness of the supply chain.


General Information


Application of the ASOE Model requires a common understanding of the following key terms:

  • Affordability
    • A determination that the LCC of an acquisition program is in consonance with the long-range investment and force structure plans of the DoD or individual DoD components.
    • Conducting a program at a cost constrained by the maximum resources that the DoD or DoD component can allocate to that capability
  • Operational Suitability - The degree to which a system can be satisfactorily placed in field use, with consideration given to reliability, availability, compatibility, transportability, interoperability, wartime usage rates, maintainability, safety, human factors, manpower supportability, logistics supportability, documentation, environmental effects, and training requirements
  • Operational Effectiveness  - is the overall degree of mission accomplishment of a system when used by representative personnel in the environment planned or expected for operational employment of the system considering organization, training, doctrine, tactics, survivability or operational security, vulnerability, and threat

Achieving ASOE

The Program Manager (PM) can address the Return on Investment (ROI) of ‘up-front’ expenditures by designing for the optimal balance between performance (technical and supportability), LCC, schedule, and process efficiency. A development program that targets only some categories of technical performance capability; or fails to optimize system Reliability, Availability, and Maintainability (RAM) technical performance, risks financial burden during the Operations and Support (O&S) Phase. The PM should therefore design for the optimal balance between technical performance (including RAM), categories of LCC, schedule, and process efficiencies. The ASOE model concept is important because it is what the user sees in terms of how well the system is able to perform its missions over a sustained period as well as the ability to surge given the user's operating budget. In this concept the emphasis is not only on the system's ability to execute its mission or its reliability and maintainability, but also on the cost effective responsiveness of the supply chain. The challenge is in how to relate these interrelated elements into an integrated shared vision across the wide range of stakeholders. The major elements impacting a system's ability to perform its mission that should be considered in the design process are depicted in Figure 1 and addressed below:


Figure 1. ASOE Model 

Major Performance Elements to Consider in the Design Process

  • Mission Effectiveness is critical because it reflects the Warfighter's ability to accomplish the mission (including the number of systems/sorties required to accomplish the mission) and directly impacts their workload. It reflects the balance achieved between the design and the process efficiencies used to operate and support the system, including the product support package and the supply chain. In addition, each of its elements directly influences the life-cycle cost. The key is to ensure mission effectiveness is defined in terms meaningful to the Warfighter over a meaningful timeframe. (e.g., number of systems required to move X ton miles in a 30 day period, or number of systems required to provide continuous surveillance coverage over 60,000 square mile area for a 6 month period).
  • Design Effectiveness - reflects key design features - technical performance and supportability features. These system aspects should be designed-in synergistically and with full knowledge of the expected system missions in the context of the proposed system operational, maintenance, and support concepts. To be effective, technical performance and supportability objectives should be defined in explicit, quantitative, testable terms. This is important to facilitate trade-offs as well as the selection and assessment of the product and process technologies. Each of the major elements controlled by the program manager in the design process is addressed below.
  • Technical Performance - is realized through designed-in system functions and their corresponding capabilities. In this context, functions refer to the desired mission abilities the system should be capable of executing in the operational environment. This includes high level functions such as intercept, weapons delivery, electronic jamming, surveillance, etc. down to the lowest subsystem level supporting functions (e.g., process signal). Capabilities refer to the various desired performance attributes and measures, such as maximum speed, range, altitude, accuracy (e.g., "circular error probable") down to the lowest subsystem level (e.g., frequencies). Each of these must be prioritized and traded off to achieve an acceptable balance in the design process.

In the ASOE context, supportability includes the following design factors of the system and its product support package:

  • Reliability - is the ability of a system to perform as designed in an operational environment over time without failure.
  • Maintainability - is the ability of a system to be repaired and restored to service when maintenance is conducted by personnel using specified skill levels and prescribed procedures and resources (e.g., personnel, support equipment, technical data). It includes unscheduled, scheduled maintenance as well as corrosion protection/mitigation and calibration tasks.
  • Support Features - include operational suitability features cutting across reliability and maintainability and the supply chain to facilitate detection, isolation, and timely repair/replacement of system anomalies. It also includes features for servicing and other activities necessary for operation and support including resources that contribute to the overall support. Traditional factors falling in this category include diagnostics, prognostics (see the Conditioned Based Maintenance (CBM) Guidebook), calibration requirements, many Human Systems Integration (HSI) issues (e.g. training, safety, Human Factors Engineering (HFE), occupational health, etc.), skill levels, documentation, maintenance data collection, compatibility, interoperability, transportability, handling (e.g., lift/hard/tie down points, etc.), packing requirements, facility requirements, accessibility, and other factors that contribute to an optimum environment for sustaining an operational system.
    • Supportability features cannot be easily "added-on" after the design is established. Consequently supportability should be accorded a high priority early in the program's planning and integral to the system design and development process. In addition to supportability features, the associated product support package, along with the supply chain, are important because they significantly impact the processes used to sustain the system, allowing it to be ready to perform the required missions.
    • While not specifically identified in Figure 2, producibility (i.e. the degree to which the design facilitates the timely, affordable, and optimum-quality manufacture, assembly, and delivery) can also impact supportability. This is because easily producible items are normally faster to obtain and have lower life-cycle costs.
  • Process Efficiency - reflects how well the system can be produced, operated, serviced (including fueling) and maintained. It reflects the degree to which the logistics processes (including the supply chain), infrastructure, and footprint have been balanced to provide an agile, deployable, and operationally effective system. While the PM does not fully control this aspect, the program directly influences each of the processes via the system design and the fielded product support package. Achieving process efficiency requires early and continuing emphasis on the various logistics support processes along with the design considerations. The continued emphasis is important because processes present opportunities for improving operational effectiveness even after the "design-in" window has passed via lean-six sigma, supply chain optimization and other Continuous Process Improvement (CPI) techniques. Examples of where they can be applied include supply chain management, resource demand forecasting, training, maintenance procedures, calibration procedures, packaging, handling, transportation and warehousing processes.

Interface of ASOE Elements 

Figure 2 below illustrates how the basic system operational effectiveness elements interface. For example, each of the supportability elements influences the process aspects which in turn can impact supportability. (e.g., while reliability drives the maintenance requirements, the implemented maintenance processes and the quality of the spare and repair parts as reflected in the producibility features can impact the resultant reliability.) In addition, how the system is operated will influence the reliability and both can be influenced by the logistic processes. Last but not least, each of the design and process aspects drives the LCC. Achieving the optimal balance across these complex relationships requires proactive, coordinated involvement of organizations and individuals from the requirements, acquisition, logistics, and user communities, along with industry. Consequently, because of the complexity and overlapping interrelationships full stakeholder participation is required in activities related to achieving affordable mission effectiveness. Models that simulate the interactions of the elements, as depicted in Figure 2, can be helpful in developing a balanced solution.


Figure 2. ASOE Interrelationships

Each of the elements reflected in Figure 1 contribute to achieving the top level affordable operational effectiveness outcome and have associated metrics which can be measured to assess efficiency and effectiveness. However, the elements cannot be mathematically added as implied in the figure. In addition to their complex interrelationships illustrated in Figure 2, the multiple stakeholders will likely only measure the portions of the supply chain as applied to their requirements, and may use different metric definitions to describe their processes. Consequently DoD has adopted the Sustainment Key Performance Parameter (KPP), its two Key System Attributes (KSA) of Reliability (R) and O&S cost and the Mean Down Time (MDT) outcome metric for projecting and monitoring key affordable operational effectiveness performance. These KPPs and KSAs:

  • Provide a standard set of measures to estimate and assess affordable operational effectiveness over time
  • Complement the traditional readiness metrics to help overcome the overlapping interrelationships
  • Provide a common communications link across the diverse systems and organizations
  • Provide the programs latitude in determining the optimum solution

Minimum Set of Sustainment Metrics 

Figure 3 below includes the minimum set of sustainment metrics the PM should use to facilitate communication across the stakeholders and the elements affecting them. The color code indicates the elements measured by the Materiel Availability (Am), R, O&S cost and MDT metrics. The metrics are interrelated, and along with the Concept of Operations (CONOPS), impact the LCC and affordability. The balanced interaction of mission effectiveness and cost (LCC/O&S/affordability) results in the achievement of an ASOE outcome.


Figure 3 Sustainment Metrics and ASOE


The overarching ASOE Model provides a structure to investigate the available trade space for requirements, engineering, and product support, and for assisting in the maximization of overall operational effectiveness goals. It is useful to help articulate and communicate the inputs and outputs of trade space decisions, and thus illuminate what the estimated performance is based upon. It is critical to clarify this information because trade-offs outside the trade space (such as program parameter changes) can require approval of both the Milestone Decision Authority (MDA) and the specific DoD or Service-specific validation authority once the KPP threshold values are established. Therefore, programs need to determine their design trade space and sustainment metrics early in the life cycle and must to ensure that the trade space and metrics are acceptable to the user and acquirer communities. Additionally, to help ensure the goals are met, the program should also establish metrics and trade space for other supporting sustainment cost and performance drivers (e.g., logistics footprint, manning levels, and ambiguity rates for diagnostics) that are uniquely tailored for the system and the projected operating environment.